Tumor diseases characterized in abnormally controlled cell proliferation are a leading cause of death for humans and other mammals. Cancer chemotherapy has provided novel and effective drugs to treat such diseases, and as a result, it was proved that the medicine for inhibiting formation of microtubules is also effective in inhibiting proliferation of tumor cells (see Mol Cancer Ther. 5, 60-67, 2006; J. Med. Chem., 48, 6107-6116, 2005; PNAS, 102, 4353-4358, 2005; Curr Pharm Des. 11, 1655-77, 2005; Cell. Mol. Life. Sci. 62, 3039-3056, 2005; and Nature Cancer Reviews 4, 253-265, 2005). Microtubules serve a very important role in regulation of cell architecture, division and metabolism. The microtubule system of eukaryotic cells includes a dynamic state of assembly and disassembly that forms microtubules in both tumor cells and normal cells by polymerization of different kinds of tubulin dimers. In tumor cells, tubulins are polymerized into microtubules to form a mitotic spindle. Subsequently, when the use of the mitotic spindle is terminated, it is depolymerized. Inhibition of the microtubule formation inhibits normal dynamic reorganization of the microtubule network that is essential for vital interphase and mitotic cellular functions. In addition, drugs for inhibiting cell proliferation in the tumor cells by discontinuing polymerization or depolymerization of microtubules occupy a part of the most effective chemotherapeutic drugs used for cancers (U.S. Pat. No. 6,962,929; WO 04/002965; WO 04/054498; WO 99/34788; and U.S. Pat. No. 6,720,331). Cell toxicity and antitumor characteristics included in the benzophenone derivatives of the present invention are derived from the ability to promote cell death (programmed cell suicide) by inhibiting microtubule assembly from tubulin dimers so as to prevent microtubule polymerization.
Psoriasis, a common chronic skin disease characterized by the presence of dry scales and plaques, is regarded as a result of abnormal cell proliferation. The disease results from hyperproliferation of the epidermis and incomplete differentiation of keratinocyte. Psoriasis is often generated in the scalp, elbows, knees, back, hips, nails, eyebrows, and genitals, and may range in severity from mild to extremely debilitating. In the end, psoriasis is progressed to psoriatic arthritis, pustular psoriasis, or exfoliative psoriatic dermatitis. Treatments for psoriasis have yet to be established. Milder cases are often treated with topical corticosteroids. However, more sever cases may be treated with antiproliferative agents, such as the antimetabolite (methotrexate), a DNA synthesis inhibitor (hydroxyurea), and a microtubule disrupter (colchicines).
Other diseases associated with an abnormally high level of cell proliferation include restenosis, where vascular smooth muscle cells are involved, inflammatory disease such as glomerulonephritis, transplant rejection, where endothelial cells are involved, infectious disease such as HIV infection and malaria, where specific immune cells and other infected cells are involved, and the like. Infectious and parasitic pathogens per se (e.g., bacteria, trypanosomes, fungi, etc.) are also subjected to selective proliferative control using the compositions and compounds of the present invention (see WO 98/05315).
The present inventors have earnestly and intensively conducted research to treat the above-mentioned diseases. As a result, the present inventors have developed a novel derivative different from the well-known compounds, and completed the present invention.